Mr Pollock, who said he has to visit his daughter in the cemetery now, said: "It's not about gun laws right now. We need our children safe."

Student Sam Zeif, 18, told how he texted his mother and two brothers during the shooting saying he wouldn't see them again before realising his 13-year-old brother was in the classroom above him, where teacher Scott Beigel died shielding students from bullets.

Video:'I visit my daughter in the cemetery now'

The teenager said: "I don't understand why I can still go in a store and buy a weapon of war, an AR. Let's never let this happen again please, please."

Florida shooting survivor Lorenzo Prado emotionally explained how he feared for his life after being held at gunpoint by six SWAT team members when he was mistaken for the gunman.

Similar clothes, hair colour and facial structure to Cruz led him to be "tossed to the ground and handcuffed" before his real identity was discovered.

Video:'I want to feel safe in my school'

The mother of a six-year-old Sandy Hook victim, Nicole Hockley, urged the President to use his time in office to stop school shootings happening.

Talking about her late son Dylan, she said: ""Every parent who sends their child to school should know without any question they're going to be coming home that day.

"How many more deaths as a country can we take? How many more teenagers and six and seven-year-olds can we allow to die? Don't let that happen anymore on your watch."

Video:'How many more deaths can we take?'

Darrell Scott, the father of a girl killed in the 1999 Columbine shooting, told how Rachel was shot, while her brother had a gun pointed at him as he lay covered with blood from his slain friends.

His son's life was only saved when the two killers were distracted by an emergency alarm going off.

At the same time in Tallahassee, Florida, thousands of students marched into the state Capitol, calling for changes to gun laws, a ban on assault-type weapons and improved care for the mentally ill.

Image:Thousands marched in in Tallahassee, Florida, calling for tighter gun control

More than 100 survivors from the Marjory Stoneman attack took part, including school senior Delaney Tarr who warned lawmakers that they "were coming after them".

Image:Senior Delaney Tarr told lawmakers: 'We're coming to get you'

She told reporters at the Capitol: "We know what we want. We want gun reform. We want common sense gun laws. We want change.

"We've had enough of thoughts and prayers. If you supported us, you would have made a change long ago.

"So this is to every lawmaker out there: No longer can you take money from the NRA.

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"We are coming after you. We are coming after every single one of you, demanding that you take action."

As the march took place, a 17-year-old student from Godby High School was arrested after writing on Instagram that he was going to "shoot up" the school.